1. Field of the Invention
The present invention relates to an image forming apparatus, and more particularly to an image forming apparatus capable of effectively performing a maintenance operation by increasing operability of a roller device.
2. Description of the Related Art
Conventionally, an image forming apparatus, such as a copier, a printer, a facsimile, or a multi-function device, which uses an electrophotographic method, generally employs a transfer roller as a mechanism to transfer a toner image formed on a surface of an image carrier onto a recording member. The transfer roller includes a metal core and a conductive elastic body layer. The conductive elastic body layer is made of conductive rubber, conductive sponge, etc., and is integrally formed in a roller shape around the metal core.
The transfer roller is rotatably supported on both ends thereof by shaft receiving members, and contacts, with pressure, the surface of the image carrier. When the recording member is passed through a nip portion between the transfer roller and the surface of the image carrier, the transfer roller is applied with a polarity opposite to a charged polarity of the toner image. Thus, the toner image is transferred onto a surface of the recording member.
In this regard, since the conductive elastic body layer of the transfer roller contacts, with pressure, the surface of the image carrier, the conductive elastic body layer of the transfer roller is worn out in continuous use. A surface of the conductive elastic body layer of the transfer roller is abraded due to a difference in linear velocity between the transfer roller and the image carrier. In addition, attachment of toner or paper dust may cause a change in a surface property of the conductive elastic body layer, thereby deteriorating transfer performance thereof and image quality.
For these reasons, the transfer roller is generally configured to be attachable to and detachable from an image forming apparatus so as to be quickly replaced with a replacement transfer roller when the transfer roller is degraded.
So far, a replacement operation of such a roller member in the image forming apparatus has been generally performed by technical support staff familiar with replacing transfer rollers. That is, general users have hardly performed the replacement operation. As a result, not much attention has been paid to operability of a replacement roller member in the replacement operation thereof.
However, general users are increasingly performing the replacement operation by themselves for some reasons, such as saving on maintenance costs of an image forming apparatus. Therefore, an increase in operability of the replacement roller member is desired so that general users may properly and effectively perform the replacement operation thereof.